1. Field of the Invention
The present invention relates to a self-adjustable universal spanner which may fasten or loosen a bolt or nut simply, continuously and efficiently without the spanner head being deviated from the bolt or nut, by rotating the bolt or nut just one direction when the spanner head is repeatedly rotated clockwise and counterclockwise direction, such as a ratchet spanner, with the head being combined with the hexagonal head of the bolt or nut. And the invention may be applied to bolts or nuts having hexagonal heads of several adjoining dimensions.
More specifically, the present invention relates to a self-adjustable universal spanner which is comprised of: a spanner head member having a jaw means for seating a bolt head and a feed groove means, wherein the jaw means includes the flat contact surface which is in surface contact with the flat surface of the bolt head in the front lower of the jaw means, and includes an escape curved surface and a slope surface for vertex contact in the rear of the flat contact surface, wherein the feed groove means includes a spring insert groove with a pin escape groove being installed in the rear thereof and includes a guide groove for deviation prevention with a escape slope surface being installed in the tip thereof; a brake piece member having a slope contact surface, a slope surface for slip prevention, a guide protrusion and a elastic support pin, wherein the slope contact surface is formed in the tip of the member, and the contact surface for slip prevention is formed in the rear bottom of the flat contact surface, and the guide protrusion has a deviation preventing shoulder protrusively installed in the length direction, and the support pin is provided in the rear of the member, wherein the member is slidably inserted in the feed groove means of the spanner head; and a deviation preventing pin which keeps the brake piece member from deviating by being inserted in front of the guide groove for deviation prevention. Thus, using the invention, the bolt or nut may be loosened or fastened continuously by rotating the spanner head member clockwise and counterclockwise with only one combining work without the spanner head being detached from or in contact with the bolt head.
2. Description of the Prior Art
In general, when making use of a common spanner for fastening and loosening a bolt or nut having a hexagonal head, a bolt or nut may be fastened and loosened by rotating the handle of the spanner in one direction. Thus, whenever rotated using said spanner, a bolt or nut has to be detached from the spanner head combined with the hexagonal head thereof. Thereafter, the combining position is adjusted and the work is repeated which fits and rotates the bolt or nut. As mentioned above, there are inconveniences in use. Since most of sizes of the bolt insert grooves in the spanner heads are fixed according to the sizes of the bolt head or nut, the spanner which corresponds to the size of the bolt head or nut must be prepared so that the preparation or use of the spanner occurs to be inconvenient. When, in the same work position, the spanner is applied and used to several adjoining dimensions of the bolt heads and nuts, each spanner which corresponds to each size has to be replaced and used. Therefore, there are inconveniences and troubles of preparing and replacing with several sizes of spanners at work and so on.
And, There is a spanner, so called a monkey spanner, which may adjust the size of the spanner according to that of the bolt head or nut. This spanner has an advantage to be made use of without limitation of the size of the bolt head. However, since the work for detaching and combining the spanner head from the bolt head or nut has to also be repeated at every fastening or loosening work of the bolt, the use of such a spanner has an inconvenient demerit like a common spanner. In use, since this spanner makes a problem that a gap between a fixed jaw and a movable jaw is changed with ease, the gap has to be readjusted with frequency.
Therefore, in order to solve the inconveniences and demerits mentioned above, it has usually been prevailed that a hexagonal bolt head or nut is fastened or loosened with the spanner repeating the clockwise and counterclockwise rotation just like the ratchet type. However, since it is made up of ratchet gears and many complicated parts, the manufacturing cost is increased so that customer gets to feel an economic burden. When the structural vulnerableness emerges into a problem by handling negligence in use, the spanner is easily out of order. Since the size of socket combined with a hexagonal bolt head or nut has already been standardized and fixed, it is of inconvenience that the socket has to be replaced to use according to the head size of the hexagonal bolt or nut. And, since it is apprehended that the socket disassembled would be lost, user has to pay attention to its treatment. In case of the bolt with a distorted head, since the socket of the spanner is not fitted to the bolt head, such a spanner can't be used to the hexagonal bolt or nut with a distorted head. As mentioned above, there are several problems in use of such a spanner.
To consider such problems, the spanner invented by the present inventor has been patented to U.S. Pat. No. 6,202,516 and U.S. Pat. No. 5,579,667 and so on, wherein said spanner may be applied uniformly to several sizes of hexagonal bolts or nuts having a fine difference of dimension. However in case of U.S. Pat. No. 6,202,516, the movable piece of the brake member is slidably installed with a spring by passing through the pin insert hole in the rear of the cut-off groove formed in the spanner head, and then passing through the screw, and  typed move preventing piece is combined with and fixed to the pin. Thus, it is difficult and hard to machine the head, which becomes an economic burden to increase in the manufacturing cost. Since  typed move preventing piece is exposed outside of the head, there is a vulnerable problem in terms of durability. And, in case of U.S. Pat. No. 5,579,667, in spite of the stability of its function, the whole construction is complicated so that the manufacturing cost is high, which restricts its mass production.